Moldable golf tee and method of making same

ABSTRACT

A method of manufacturing a golf tee includes a step of molding a shaft using a first moldable material. The method also includes molding an upper portion of the tee using a second moldable material. The upper portion has a ball receiving structure. A portion of either the shaft or the upper portion is used as a part of a mold for the molding of the other of the shaft or the upper portion.

FIELD OF THE INVENTION

The present invention relates generally to golf tees, and particularly to golf tees made from moldable materials.

BACKGROUND

Golf tees are made from a plurality of different materials. For example, golf tees are constructed of wood, plastic, and occasionally even metal such as aluminum. Tees made from wood basically consist of a unitary structure having a shaft portion and a golf ball holding upper portion. In use, the shaft is placed in the ground and the ball is placed on top of the upper portion. To this end, the shaft typically includes a pointed tip that facilitates insertion into the ground, and the upper portion typically includes a wider concave surface that facilitates retention of the ball. Such tees are commonplace.

Wood tees have many benefits, including light weight and biodegradability. Wooden tees typically have a simple design which is well known. Because of the nature of wood, it is not practical to use any design that varies substantially from the traditional design. Thus, it is difficult to employ enhanced design features in wooden tees.

Plastic tees, by contrast, are formed from molding machines, which allows for more variation in physical configuration. In the past, inventors have taken advantage of the flexibility of plastic manufacturing process to incorporate design features into tee configurations. By way of example, U.S. Pat. No. 5,242,170, U.S. Pat. No. 4,998,732, U.S. Pat. No. 6,849,008, U.S. Pat. No. 6,942,583, and U.S. Pat. No. 7,011,581 all disclose tees in which at least a portion is formed from plastic, thereby facilitating advanced design elements not present in traditional wood tees.

Despite the advances in golf tee design, simple wooden tees remain the most popular. Moreover, the only plastic tees that have gained any substantial acceptance are relatively simple and incorporate little or no advanced components.

At least one probable reason for lack of advancement of some tee designs is that these designs result in a very unconventional tee appearance that can be intimidating or at least displeasing to many golfers. Another reason for the lack of advancement of some tee designs is that they include several parts that must be assembled, thereby greatly increasing the cost of the tee.

There is a need therefore, for a golf tee that addresses one or more of the shortcomings of the prior art discussed above.

SUMMARY

Disclosed embodiments of the invention address at least some of the above issues by providing a golf tee having a shaft formed of a first moldable material and an upper portion formed of a second moldable material. In some embodiments, the golf tee is formed by overmolding one of the structures onto the other. In other embodiments, the molded pieces of different materials allow for one or more advanced features to be readily incorporated into the design.

A first embodiment of the invention is a golf tee having a shaft and an upper portion. The shaft is constructed or formed from a first moldable material The upper portion is formed from a second moldable material, and is moldably affixed to the shaft.

A second embodiment of the invention is a method of manufacturing a golf tee that includes a step of molding a shaft using a first moldable material. The method also includes molding an upper portion of the tee using a second moldable material. The upper portion has a ball receiving structure. A portion of one of the shaft and the upper portion is used as a part of a mold for the molding of the other of the shaft and the upper portion.

The above described features and advantages, as well as others, will become more readily apparent to those of ordinary skill in the art by reference to the following detailed description and accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a perspective view of an exemplary golf tee according to embodiments of the invention;

FIG. 2 shows a top plan view of the golf tee of FIG. 1;

FIG. 3 shows a side plan view of the golf tee of FIG. 1;

FIG. 4 shows a side cutaway of the tee of FIG. 1;

FIG. 5 shows a perspective view of the a cavity side of a mold suitable for carrying out an exemplary method according to the invention; and

FIG. 6 shows a perspective view of the a core side which cooperates with the cavity side of FIG. 5 to form the mold suitable for carrying out an exemplary method according to the invention.

DETAILED DESCRIPTION

FIGS. 1-4 show different views of an exemplary embodiment of a golf tee 10 according to at least some embodiments of the present invention. The golf tee 10 is given by way of example only. It will be appreciated that there are many variations of golf tees that fall within the ordinary plain meaning of the terms used in the claims. Unless otherwise specified, the words used in the specification are intended to have a generic meaning and are not meant to be limited to the embodiments described herein. Moreover, different embodiments of the invention may have different advantages. Advantages described herein should never be construed to cover each and every embodiment of the claimed invention.

FIG. 1 shows an exemplary embodiment of a golf tee 10 that incorporates features of the invention. The golf tee 10 includes a shaft 12 and an upper portion 14. The shaft 12 is a generally rigid, elongated member that is configured for placement into the ground. In this embodiment, the shaft 12 is first unitary structure of a first moldable material, which may suitably be a material primarily composed of nylon, polypropylene, polycarbonate and ABS. The shaft 12 is preferably slightly tapered along its length, preferably ending at a first end at a pointed tip 16. The purpose of the taper of the shaft in this embodiment is two-fold. Firstly, the taper allows the shaft to be more readily extracted from a mold (see FIGS. 5-8, discussed below). Secondly, the taper defines the pointed tip 16. It is advantageous in some embodiments to have a gradual taper for most of the length of the shaft 12 and an increased taper near the pointed tip 16. However, it will be appreciated that many advantages of the invention may be obtained regardless of whether any taper is provided.

The upper portion 14 is intended to form a support for a golf ball. To this end, the upper portion 14 includes an axially upper most and radially outward rim or edge 18 defined on a first annular member 20 that receives the golf ball, not shown. The upper portion 14 also includes a second annular member 22 affixed to a second end of the shaft 12. A set of three trusses or support members 24 are connected to each of the first annular member 20 and the second annular member 22 to provide support to the first annular member 20.

This type of Tee construction is less likely to fracture while being struck by a golf club, which is often the case with Tees of other materials such as wood and of other plastic designs. Both the trussed design and the choice of soft material for the upper portion enhance the ability of the Tee so survive impact by a golf club.

In the embodiment of FIGS. 1-4, the first annular member 20 includes a lower annular portion 26 having a generally cylindrical inner annular wall 28 and an inclined outer annular wall 30. The first annular member 20 also includes an upper portion 32 having a generally cylindrical outer annular wall 34 and an inclined inner annular wall 36. The above described configuration of the upper annular portion defines a concavity for receiving the round golf ball.

The support members 24 generally incline upward an outward from the second annular member 22 to the bottom and the generally inner annular wall 28 of the lower annular portion 26 of the first annular member. The support members 24 are spaced apart around the circumference of the second annular member 22, forming through-holes 25 or openings in upper portion 20. In some embodiments, the support members 24 may extend continuously around circumference of the tee 10 such that the first annular member 20, the second annular member 22, and the support member 24 forms a solid, continuous surface. However, inclusion of at least one interruption, through-hole or other type of void is advantageous in many embodiments because it increases flexibility and/or reduces material costs, while retaining structural integrity. The use of voids such as through-holes may also provide relief from non-uniform stress in the upper portion 14.

In general, the upper portion 14 as described above, and/or in other embodiments, comprises a unitary structure of a second moldable material which is different from the first moldable material of the shaft 12. The use of two different moldable materials provides for different advantages in different embodiments, but generally allows for the versatility of using molded parts (as opposed to carved or cut wood), and the versatility provided by using different materials and/or injection steps for the two parts of the tee that serve different functions.

In some embodiments, the upper portion 14 and the shaft 12 are connected by bonds formed at the interface therebetween. The interface between the upper portion 14 and the shaft 12 lies at the upper end of the shaft and the inner surface of the second annular portion 22. The bond connection may suitably be formed by molding the upper portion 14 onto the shaft 12, as discussed below in connection with FIGS. 5-8, or vice versa.

In some embodiments, the second moldable material of the upper portion 14 is relatively flexible such that it elastically deforms relatively easily to the touch. In such embodiments, the upper portion 14 may flex and deform upon impact of the golf club, not shown, on the golf ball placed on the tee 10. To this end, in some embodiments, the second moldable material is more flexible than the first flexible material, and may suitably be primarily thermoplastic elastomer, urethane or silicone.

Flexibility of the upper portion 14 can in some cases provide various advantages, such as improved ball release. In addition, some elastically deformable materials such as GLS Dynaflex have a slightly tacky quality that may enhance golf ball spin during flight. No one of these particular advantages is critical to all embodiments of the invention. At least some of the advantages of using a unitarily formed upper portion of a second moldable material that is more flexible than the first moldable material of the shaft may be obtained even if the upper portion and shaft are not overmolded or connected by bond.

As discussed above, the “trussed” design of the upper portion 14 of the tee 10 formed by the through-holes 25 may enhance the flight characteristics of the golf ball, as there is less structural resistance because of the voids, as there would be in a solid tee. This is particularly true if the upper portion 14 is flexible. Moreover, by using a soft or lower durometer material for the upper portion 14, the upper portion 14 is also less likely to damage the face of gold clubs.

In still other embodiments, the first moldable material and the second moldable material may be structurally similar, but differ in color. In such a case, the upper portion 14 would be a first color and the shaft 12 would be a second color. This embodiment may be used to economically provide tees having color schemes corresponding to or symbolizing a school, club, nation or other collective group.

FIGS. 5-6 illustrate a molding arrangement that may be used to form tees such as the tees 10 in accordance with an exemplary method according to the present invention. While the exemplary method described herein references the structures of the tee 10 of FIGS. 1-4 for clarity of exposition, it will be appreciated that the exemplary method described herein is not limited to use in manufacturing the tee 10 of FIGS. 1-4. Conversely, the various embodiments of the tee 10 described above need not be manufactured using the exemplary method described herebelow.

In this exemplary method, the tees are formed in a two-material overmolding process, wherein the upper portion 14 is formed in one station of the mold, and the shaft 12 is formed in another station. In the exemplary embodiment described herein, the shaft 12 is formed in a first operation and the upper portion 14 is overmolded onto the shaft 12. In this embodiment, the two materials used bond chemically to each other.

Referring now to FIGS. 5-6, the mold basically consists of a cavity side 102 (See FIG. 5) and a core side 104 (See FIG. 6). The cavity side 102 includes two stations 106 and 108, each having four cavities 110 and 112 respectively. Each of the cavities 110 of the first station 106 have a shape that is inverse to the outer surface of the shaft 12, and each of the cavities 112 of the second station have a shape that is inverse to the outer-most surfaces of the upper portion 14. Thus, the cavities 112 in the exemplary tee 10 of FIGS. 1-4 define the inverse of the inclined outer annular wall 30 and outer annular wall 34 of the upper portion 14, and further define the inverse of the outer surface of the second annular member 22. The cavity side 102 is generally configured to inject molten material into the cavities 110 and 112 as is generally known in the art.

The core side 104 includes two substantially identical core stations 118 and 120. the core stations 118 and 120 are arranged on a rotatable mount 122. Each of the core stations has a core assembly 124. Each core assembly 124 includes structures that define the interior surfaces of the through-holes 25 of the upper portion 14 and the inverse of the support members 24. The core assemblies 124 also include a center post 126 that defines a hollow central cavity of the shaft 12.

In operation, the first station 106 of the cavity side 102 cooperates with one of the core stations 118, 120 to form the shafts (12) of four tees (10), while the second station 108 of the cavity side 102 cooperates with the other of the core stations 118, 120 to form the upper portions (14) on top of previously molded shafts (12). These operations occur concurrently. Thus, for a particular tee, the shaft 12 is first molded, extracted from the first cavity 110, then inserted into a cavity 112 of the second station 108. In the cavity 112, the upper portion 14 is molded onto the shaft 12. Thereafter, the finished tee is ejected.

To accomplish the foregoing, the rotatable core side 104 is positioned such that the core station 118 is generally aligned with and facing the first station 106 of the cavity side 102, and more specifically, such that the cavities 110 are aligned with the core assemblies 124 of the core station 118. In this position, the core assemblies 124 of the core station 120 are similarly aligned with the cavities 112 of the second station 108. The core assemblies 124 of the core station 120 have completed shafts (2) from a previous molding step formed thereon.

The core side 104 is then moved toward the cavity side 102 such that they abut each other, at which point the center posts 126 of the core assemblies 124 are inserted into the cavities 110, and the center posts 126 and molded shafts are inserted into the cavities 112. With specific reference to the first station 106, each core assembly 124 and its respective cavity 10 exactly defines the inverse of hollow shaft 12. Molten material is injected into each cavity 110 and allowed to solidify thermally. In the embodiment described herein, the molten matter may be cooled via water cooled metallic mold materials transferring heat from the polymers. The result is a newly molded shaft 12.

With specific reference to the second station 108, each core assembly 124 and respective cavity 112 defines, along with an upper portion of the shaft 12, the inverse of the upper portion 14. It is noted that upper portion of the shaft 12 forms a part of the “core” that defines the inner surface of the second annular member 22 of the upper portion 14. Otherwise, structures of the core assembly 124 and the cavity 112 define the remaining structures of the upper portion 14. Molten material is similarly injected into each cavity 112 and allowed to solidify. The temperature of the second molten material must be at a temperature that actuates bonding of the two materials, but does not degrade the previously injected material. By way of non-limiting example, if the shaft 12 is polypropylene, and the upper portion 14 is thermoplastic elastomer (“TPE”), then the temperature of the molten TPE may suitably be 400° F.

The materials and temperature in one embodiment are selected such that a bond is formed at the interface between the upper portion 14 and the shaft 12. However, in an alternative embodiment, the shaft 12 and upper portion 14 may be selected to having mechanical retention (i.e. interlocking) elements. However, mechanical retention elements can significantly increase the complexity of the mold as they typically require undercuts.

Thus, after the above described molding step, the first station 106 generates four shafts of four tees on the core assemblies 124 of the core station 118 and the second station 108 generates four upper portions overmolded onto four previously formed shafts. As a result, the core assemblies 124 of the core station 120 contain completed tees.

After this molding step, the rotating core side 104 is moved axially away from the cavity side 102, and the four completed tees on core station 120 are ejected from the core assemblies 124 of the core station. The rotating core side 104 then rotates such that now-empty core assemblies 124 of the core station 120 are aligned with the cavities 110 of the first station 106, and that the shaft-bearing core assemblies 124 of the core station 118 are aligned with the cavities 112 of the second station 108. So aligned, the rotating core side 104 is moved axially toward the cavity side 102 and the above molding operations are repeated with the new rotational position of the core side 104.

These operations are repeated such that two molding steps are required for each tee 10, and such that four tees are generated for each molding step. The exemplary method described above eliminates assembly operations, automated or manual, which increase cost and complexity, without removing the advantages of using different moldable materials for the shaft 12 and upper portion 14 of the tee.

It will be appreciated that the above describe embodiments are merely exemplary, and that those of ordinary skill in the art may readily devise their own modifications and implementations that incorporate the principles of the present invention and fall within the spirit and scope thereof. For example, it will be noted that the ball receiving portion of the upper portion 14 need not include a continuous rim 18, but may instead consist of a series of structures forming an interrupted, but generally level, annulus or periphery. For example, the continuous rim 18 may be replaced by a circularly arranged series of posts, bumps or other support structures. Moreover, while the ball receiving structure of the upper portion is preferably circular in shape as shown in FIG. 2, lesser effective shapes such as rectangles, triangles or other polygons may be used and still derive the benefits of the embodiments of the present invention. In addition, there is no requirement that the shaft 12 be round, although that is the generally accepted shape. As discussed above, some embodiments of the invention do not require the specific configuration of the upper annular member 20, the lower annular member 22 and the support members 24. The upper portion 14 may take a number of other configurations, including those that only derive some of the benefit described above, while still obtaining some benefits.

It will also be appreciated that the benefits of the two material construction are more fully apparent when the shaft constitutes a majority of the tee, because it provides a rigid support. Even when support is not an issue, the use of a longer shaft than upper portion allows the tee to retain a more traditional appearance, and will therefore allow for wider acceptance in the golf audience. The longer shaft also facilitates additional flexibility in the height at which the ball is teed up. Thus, in at least some advantageous embodiments, the length (i.e. height) of upper portion 14 is less than one-half, and preferably less than one-third, of the length of the shaft 12. 

1. A golf tee, comprising: a shaft formed from a first moldable material an upper portion formed from a second moldable material, the upper portion moldably affixed to the shaft.
 2. The golf tee of claim 1, wherein the upper portion comprises a unitary structure.
 3. The golf tee of claim 2, wherein the upper portion has a length that is less than one-half of a length of the shaft.
 4. The golf tee of claim 2, wherein the upper portion has a length that is less than one-third of a length of the shaft.
 5. The golf tee of claim 1, wherein, in a molded state, the second moldable material has a greater flexibility than the first moldable material.
 6. The golf tee of claim 5, wherein the upper portion includes at least one continuous annular portion.
 7. The golf tee of claim 6, wherein the upper portion has a plurality of openings formed therein, the openings continuously surrounded by the second moldable material.
 8. The golf tee of claim 1, wherein the first moldable material and the second moldable material cooperate to form a bond at an interface there between.
 9. A method of manufacturing a golf tee, comprising: a) molding a shaft using a first moldable material b) molding an upper portion using a second moldable material, the upper portion having a ball receiving structure; and wherein a portion of one of the shaft and the upper portion is used as a part of a mold for the molding of the other of the shaft and the upper portion.
 10. The method of claim 9, wherein a portion of the shaft is used as a part of the mold for molding of the upper portion.
 11. The method of claim 9, wherein the first moldable material and the second moldable material bond to each other in one of step a) and step b).
 12. The method of claim 11, wherein the first moldable material and the second moldable material bond to each other in step b).
 13. The method of claim 9, wherein, in a molded state, the second moldable material has more flexibility than the first moldable material.
 14. The method of claim 9, wherein: the first moldable material is selected from a group consisting of nylon, polypropylene, polycarbonate and ABS; and the second moldable material is selected from a group consisting of thermoplastic elastomer (TPE), urethane and silicone.
 15. A golf tee, comprising: a shaft comprising a first unitary structure of a first moldable material an upper portion comprising a second unitary structure of a second moldable material, the second moldable material having a greater flexibility than the first moldable material, the upper portion affixed to the shaft, the upper portion including a shaft end and a ball receiving end, and wherein a diameter of the ball receiving end exceeds a diameter of the shaft end.
 16. The golf tee of claim 15, wherein the upper portion has a plurality of openings formed therein, the openings continuously surrounded by the second moldable material.
 17. The golf tee of claim 18, wherein the first moldable material and the second moldable material form a bonding connection at an interface therebetween.
 18. The golf tee of claim 15, wherein the upper portion includes a first annular member configured to receive a golf ball, a second annular member affixed at least in part to the shaft, and a plurality of support member, each connected between the first annular member and the second annular member.
 19. The golf tee of claim 18, wherein the first moldable material and the second moldable material form a bonding connection at an interface therebetween.
 20. The method of claim 19, wherein: the first moldable material is selected from a group consisting of nylon, polypropylene, polycarbonate and ABS; and the second moldable material is selected from a group consisting thermoplastic elastomer (TPE), urethane and silicone. 